Average Impulse Response help

I am building a patch for my father – who is a violin maker – where we can load violin impulse responses into a buffer, to filter a signal.

thats the easy part. now, what we want to do is : we want to be able to visualize the average spectrum of the impulse response, on a multislider or function object – to be able to edit the resulting filter (pull down peaks, or boost dips etc…) like in the famous forbidden planet patch.